CN102352874A - Digital pure water hydraulic proportional overflow valve - Google Patents
Digital pure water hydraulic proportional overflow valve Download PDFInfo
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- CN102352874A CN102352874A CN2011103368204A CN201110336820A CN102352874A CN 102352874 A CN102352874 A CN 102352874A CN 2011103368204 A CN2011103368204 A CN 2011103368204A CN 201110336820 A CN201110336820 A CN 201110336820A CN 102352874 A CN102352874 A CN 102352874A
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Abstract
The invention discloses a digital pure water hydraulic proportional overflow valve. The pure water hydraulic proportional overflow valve in China at present has the defects of narrow pressure-regulating range, great hysteresis loop, great steady state pressure-regulating deviation and the like. The overflow valve is characterized in that: firstly hydrostatic bearing grooves are respectively arranged between a guide valve core and a guide valve sleeve and between a main valve core and a main valve sleeve, thereby solving the problem that the viscosity of the pure water is lower so as to generate the thinner lubricating water film and insufficient lubrication; secondly, the characteristics that the viscosity of the pure water is lower, the gap between the guide valve core and the guide valve sleeve is easy to leak, thereby designing guide valve gap liquid resistance; and the formed guide valve pi bridge liquid resistance network is used for improving the steady state precision of the overflow valve, thereby changing the disadvantage of the pure water hydraulic proportional overflow valve into an available condition. The digital pure water hydraulic proportional overflow valve provided by the invention has the advantage of being capable of achieving the automation of pressure-regulating function of a pure water hydraulic system.
Description
Technical field
The invention belongs to fluid transmission and control technique field, relate to a kind of digital pure water hydraulics proportional pressure control valve.
Background technique
Employed driving medium-the pure water of pure water hydraulics transmission system has the not available many advantages of conventional hydraulic oil: characteristics such as environmental friendliness, purchase and user cost are low, the flame retarding Security is good, easy care maintenance, rigidity is big, temperature rise is low, this also is the reason place that the pure water hydraulics transmission receives domestic and international attention.But characteristics such as except that above-mentioned advantage, pure water has also that viscosity is low, poor, electric conductivity are strong, pressure for vaporization height, this has brought difficulty for research of pure water hydraulics drive technology.Wherein the most outstanding difficult point also is because the viscosity of pure water low (have only traditional mineral hydraulic oil viscosity 1/40-1/50); The lubricated problem of the thin influence of the pure water hydraulics lubrication film thickness that brings, and the leakage rate through identical sealing off gap will be more than 20 times of oily medium under the equal pressure reduction.So problem domains such as that the research of water hydraulic components also mainly concentrates on is lubricated, sealing, burn into cavitation erosion.
The colleges and universities that carry out the water hydraulic technical research in the world have: Tampere, Finland Polytechnics, Sweden woods snow duckweed university, Purdue Univ-West Lafayette USA, RWTH, Denmark Polytechnic University, Kanagawa, Japan university, northeastern Japan university etc.Main in the world water hydraulic element brand has: Denmark Danfoss company, Britain WaterHydraulic, German Hauhinco, Tiefenbach, U.S. Elwood, Japanese Ebara comprehensive study institute etc.Current water hydraulic technology has been widely used in fields such as water treatment, nuclear power machinery, metallurgical machinery, food machinery, forestry machinery, mining machinery, ocean development, underwater operation, fire-fighting fire extinguishing, weaponry, fire-fighting.
The electricity of hydraulic pressure proportional pressure control valve-mechanical switch actuator generally has two kinds of forms, and a kind of is to adopt proportion electro-magnet as actuator, and another kind is to adopt stepper motor as actuator.
The employing proportion electro-magnet is the hydraulic pressure proportional pressure control valve of actuator, pressure rating 14MPa, flow 100L/min; The domestic PDBV type pure water hydraulics proportional pressure control valve that German Tiefenbach company is arranged of seeing more; But there are many defectives in this type valve; Comprise defectives such as the pressure regulation range is narrow, the ring that stagnates is big, the stable state override pressure is big, its reason mainly is because problems such as low caused lubricated, the sealing of the viscosity of water do not obtain fine solution.
The research of stepper motor increment type oil pressure digital valve, comparatively leading with Japan, wherein the digital stream metered valve of Tokyo gauge company, pressure valve, directional flow control valve existing procucts; Pressure reaches 21MPa; Flow is 1-500L/min, and its repeat property precision is encircled precision all below 0.1%, the Vickers company of the U.S. with stagnating; Also there is correlated digital valve product in the oil company of grinding of Japan, but market does not still have this digital pure water hydraulics proportional pressure control valve product at home.
In the research of pure water hydraulics proportional pressure control valve, problems such as burn into cavitation erosion can be improved through the improvement of material and solve.Lubricated and sealing is the key point in the research of pure water hydraulics proportional pressure control valve.To these difficult points, have both at home and abroad to be employed in the pure water way of adding compound additive, be commonly called as the high water base fluid hydraulic fluid, reach and can satisfy requirements such as energy-conservation, that temperature rise is slow and can satisfy the requirement that appropriateness is lubricated again.But the high water base fluid hydraulic fluid has and receives contamination by micro, the more high shortcomings of cost more easily.So to fundamentally address these problems a little, also need be from the principle and the structure of valve, the pure water hydraulics proportional pressure control valve element that design has Rational structure makes it satisfy requirement lubricated and sealability.
Summary of the invention
The present invention is directed to the deficiency of existing technology, a kind of digital pure water hydraulics proportional pressure control valve is provided.
The technological scheme that technical solution problem of the present invention is taked is:
Digital pure water hydraulics proportional pressure control valve comprises electricity-mechanical transducer, the main valve of pilot valve, pilot valve.
Electricity-the mechanical transducer of described pilot valve comprises actuating motor and cam, and cam is assemblied in motor shaft through flat key.
Described pilot valve comprises push rod, guide's spring, guide's spool, pilot valve valve pocket and guide's valve seat; Cam in electricity-mechanical transducer promotes guide's spool through push rod pushing guide spring and moves; Make between its conical surface and the pilot valve valve pocket internal surface shoulder and form settable orifice; Guide's spool is made up of three cylndrical surface and a conical surface; Wherein two cylndrical surface and pilot valve valve pocket internal surface form the gap liquid resistance; And be designed with the hydrostatic bearing groove and eliminate the friction between guide's spool and the pilot valve valve pocket and realize spool centering, the cylndrical surface that another is bigger and valve pocket internal surface seal through seal ring, and the pilot valve cover is assemblied in the pilot valve seat.The actuating motor of electricity-mechanical transducer is assemblied on the pilot valve valve seat through screw.
Described main valve comprises main valve plug, main spool spring, main valve valve pocket and main valve seat; Primary valve part adopts the design of in-flow valve port; The through hollow design of the inner employing of main valve plug; The main valve plug outer surface is made up of two cylndrical surface and a conical surface; The cylndrical surface partial design have the hydrostatic bearing groove to reduce or eliminate main valve plug and the main valve valve pocket between friction and realize the main valve plug axial alignment, the main valve plug upper end is compressed by main spool spring, makes between main valve plug conical surface and the main valve valve pocket internal surface shoulder and forms settable orifice; It is inner that the main valve valve pocket is assemblied in the main valve valve seat, and the outside is sealed it by screw plug admittedly.Cavity volume between pilot valve and the main valve is communicated with the stability that improves main valve plug through fixing damping hole liquid resistance, and the communicated cavity junction is sealed by seal ring, and guide's valve seat and main valve valve seat pass through Bolt Connection.
Beneficial effect of the present invention: at first; All designed hydrostatic bearing between guide's spool and the guide's valve pocket and between main valve plug and the main valve housing, can solve because water film thickness approaches the problem of lack of lubrication, secondly; The slit that makes full use of between spool and the valve pocket causes the leakage characteristics easily; Design the gap liquid resistance, constitute guide π bridge liquid resistance network and improve stable state accuracy, thereby transfer adverse condition to available condition.Digital pure water hydraulics proportional pressure control valve can be realized the automation of pure water hydraulics system pressure regulatory function.
Description of drawings
Fig. 1 is a structural representation of the present invention.
Among Fig. 1: 1. actuating motor, 2. screw, 3. screw plug, 4. cam, 5. bearing housing; 6. bearing, 7. push rod, 8. seal ring, 9. guide's spring, 10. guide's spool; 11. the pilot valve valve pocket, 12. guide's valve seats, 13. main spool springs, 14. main valve plugs, 15. main valve valve pockets; 16. main valve seat, 17. screw plugs, P. water intake, T. water outlet.
Fig. 2 is pilot valve planing surface figure, 18～19. seal rings, a, the resistance of c. pilot valve gap liquid, the variable liquid resistance of b. pilot valve.
Fig. 3 is main valve planing surface figure, the fixedly damping hole liquid resistance of d. main valve settable orifice, e..
Fig. 4 is guide's spool planing surface figure, 20, the 21 clear hydrostatic bearing groove designs of having expressed guide's spool.
Fig. 5 is main valve plug planing surface figure, and clear hollow type of having expressed main valve plug connects the damping piston design of design and main valve plug lower end, and 22,23 is the design of main valve plug hydrostatic bearing groove.
Embodiment
Below in conjunction with accompanying drawing the present invention is described further.
As shown in Figure 1, digital pure water hydraulics proportional pressure control valve comprises electricity-mechanical transducer, the main valve of pilot valve, pilot valve.
Electricity-the mechanical transducer of pilot valve comprises actuating motor 1 and cam 4, and cam 4 is assemblied in motor shaft through flat key.
Pilot valve comprises push rod 7, guide's spring 9, guide's spool 10, pilot valve valve pocket 11 and guide's valve seat 12; Cam 4 in electricity-mechanical transducer converts rotatablely moving of actuating motor 1 straight line motion into and promotes guide's spool 10 through push rod 7 pushing guide springs 9 and moves; Make and form the variable liquid resistance of settable orifice (like b among Fig. 2) between its conical surface and the pilot valve valve pocket 11 internal surface shoulders as pilot valve π bridge liquid resistance network; Guide's spool 10 is made up of three cylndrical surface and a conical surface, and wherein two cylndrical surface and pilot valve valve pocket internal surface form gap liquid resistance (like a, c among Fig. 2).Main valve plug is designed with hydrostatic bearing groove (as among Fig. 4 20,21) and eliminates the friction between guide's spool 10 and the pilot valve valve pocket 11 and realize spool centering; Cylndrical surface that another is bigger and valve pocket internal surface are through seal ring 18 sealings (like Fig. 2), and guide's valve pocket 11 is assemblied in guide's valve seat 12.The actuating motor 1 of electricity-mechanical transducer is assemblied on the pilot valve valve seat 12 through screw 2.
Main valve comprises main valve plug 14, main spool spring 13, main valve valve pocket 15 and main valve seat 16; Primary valve part adopts the design of in-flow valve port; The through hollow design of main valve plug 14 inner employings; Main valve plug 14 outer surfaces are made up of two cylndrical surface and a conical surface; The cylndrical surface partial design has hydrostatic bearing groove (as among Fig. 5 22,23) to reduce or eliminates the friction between main valve plug 14 and the main valve valve pocket 15 and realize main valve plug 14 axial alignments; Main valve plug lower end design simultaneously is equivalent to the stability that damping piston can improve main valve plug 14, and main valve plug 14 upper ends are compressed by main spool spring 13, make between main valve plug 14 conical surfaces and the main valve valve pocket 15 internal surface shoulders and form settable orifice (like d among Fig. 3); Main valve valve pocket 15 is assemblied in main valve valve seat 16 inside, and the outside is sealed it by screw plug 17 admittedly.Cavity volume between pilot valve and the main valve is communicated with the stability that improves main valve plug 14 through fixing damping hole liquid resistance (like e among Fig. 3), and the communicated cavity junction is by seal ring 19 sealings (like Fig. 2), and guide's valve seat 12 and main valve valve seat 16 pass through Bolt Connection.
Digital pure water hydraulics proportional pressure control valve design parameter is following:
1) rated pressure can reach 14MPa and more than;
2) rated flow can reach 100L/min and more than;
3) frequency response can reach 40Hz and more than.
Digital pure water hydraulics proportional pressure control valve working principle is following:
The present invention utilizes the electricity-mechanical transducer of the mode of actuating motor and cam as pilot operated compound relief valve, can realize that the high frequency sound ratio pressure of pure water hydraulics system is regulated.Digital pure water hydraulics proportional pressure control valve has 2 hydraulic pressure connection mouths, connects high pressure water (P), water tank (T) respectively;
To actuating motor 1 sending controling instruction, control cam 4 rotates to an angle, and promotes push rod 7 and makes guide's spring 9 reach certain decrement, is equivalent to 10 1 preset pressures of guide's spool.
The pressure of pure water hydraulics system is through guide's spool 10 direct detections; When system pressure reached set pressure, guide's spool begins to move and the pilot valve conical surface (like b among Fig. 2) and pilot valve valve pocket internal surface shoulder place are become by closure to be opened, and the hydraulic pressure medium produces overflow through the slit (like a, b, c among Fig. 2) between guide's spool and the guide's valve pocket; Overflow meeting simultaneously make the resistance of pilot valve gap liquid (as among Fig. 2 a) two ends produce pressure and fall; Make main valve plug 14 upper and lower end produce pressure reduction, when pressure reduction surpassed the preset pressure of main spool spring 13, main valve plug 14 moved; The main valve plug cone valve is opened; Thereby make hydraulic system generation overflow, what of spillway discharge are the size of its main valve plug opening amount determined, thereby can guarantee that system pressure and set pressure balance each other.
The present invention has used the combination of actuating motor and cam on electromechanical transducer, realize rotatablely moving to straight-line conversion.Through designing between guide's spool and the guide's valve pocket and the hydrostatic bearing between main valve plug and the main valve housing, solve because the easy friction problem that the thin lack of lubrication of water film thickness causes.Simultaneously, it is lower to make full use of pure water viscosity, and the characteristics that leak easily in the slit between spool and the valve pocket have designed the gap liquid resistance, thereby transferred the adverse condition of pure water hydraulics to condition capable of using, improves stable state accuracy through constituting guide π bridge liquid resistance network.
Claims (1)
1. digital pure water hydraulics proportional pressure control valve comprises it is characterized in that electricity-mechanical transducer, the main valve of pilot valve, pilot valve:
Electricity-the mechanical transducer of described pilot valve comprises actuating motor (1) and cam (4), and cam (4) is assemblied in motor shaft through flat key;
Described pilot valve comprises push rod (7), guide's spring (9), guide's spool (10), pilot valve valve pocket (11) and guide's valve seat (12); Cam in electricity-mechanical transducer (4) promotes guide's spool (10) through push rod (7) pushing guide's spring (9) and moves; Make between its conical surface and pilot valve valve pocket (11) the internal surface shoulder and form settable orifice (b); Guide's spool (10) is made up of three cylndrical surface and a conical surface; Wherein two cylndrical surface and pilot valve valve pocket internal surface form gap liquid resistance (a, c); And be designed with the hydrostatic bearing groove and eliminate the friction between guide's spool (10) and the pilot valve valve pocket (11) and realize spool centering, the cylndrical surface that another is bigger and valve pocket internal surface seal through seal ring (18), and guide's valve pocket (11) is assemblied in guide's valve seat (12); The actuating motor of electricity-mechanical transducer (1) is assemblied on the pilot valve valve seat (12) through screw (2);
Described main valve comprises main valve plug (14), main spool spring (13), main valve valve pocket (15) and main valve seat (16); Primary valve part adopts the design of in-flow valve port; The through hollow design of the inner employing of main valve plug (14); Main valve plug (14) outer surface is made up of two cylndrical surface and a conical surface; The cylndrical surface partial design has hydrostatic bearing groove (22,23) to reduce or eliminates the friction between main valve plug (14) and the main valve valve pocket (15) and realize main valve plug (14) axial alignment, and main valve plug (14) upper end is compressed by main spool spring (13), makes between main valve plug (14) conical surface and main valve valve pocket (15) the internal surface shoulder and forms settable orifice (d); Main valve valve pocket (15) is assemblied in main valve valve seat (16) inside, and the outside is sealed it by screw plug (17) admittedly; Cavity volume between pilot valve and the main valve is communicated with the stability that improves main valve plug (14) through fixing damping hole liquid resistance (e), and the communicated cavity junction is by seal ring (19) sealing, and guide's valve seat (12) and main valve valve seat (16) pass through Bolt Connection.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 201110336820 CN102352874B (en) | 2011-10-31 | 2011-10-31 | Digital pure water hydraulic proportional overflow valve |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 201110336820 CN102352874B (en) | 2011-10-31 | 2011-10-31 | Digital pure water hydraulic proportional overflow valve |
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| CN102352874A true CN102352874A (en) | 2012-02-15 |
| CN102352874B CN102352874B (en) | 2013-12-25 |
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| Application Number | Title | Priority Date | Filing Date |
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| CN 201110336820 Expired - Fee Related CN102352874B (en) | 2011-10-31 | 2011-10-31 | Digital pure water hydraulic proportional overflow valve |
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Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102829010A (en) * | 2012-08-16 | 2012-12-19 | 北京润菲利德科技有限公司 | Directly moving type high-flow directional flow servo valve and control system using servo valve |
| CN103047291A (en) * | 2012-12-28 | 2013-04-17 | 扬州锻压机床股份有限公司 | Lubricating oil fine-tuning and throttling structure of precise hydrostatic bearing |
| CN104196793A (en) * | 2014-07-31 | 2014-12-10 | 红安安达新材料有限责任公司 | Overflow valve |
| CN109027222A (en) * | 2018-10-24 | 2018-12-18 | 扬州荣德新能源科技有限公司 | A kind of piston and the proportioning valve including it |
| CN109555740A (en) * | 2018-11-09 | 2019-04-02 | 太原理工大学 | A kind of water base proportioning valve and its control method |
| CN109798273A (en) * | 2019-03-18 | 2019-05-24 | 杭州诺祥科技有限公司 | A kind of flux matched formula balance fastening system of asymmetric drift |
| CN117509816A (en) * | 2024-01-05 | 2024-02-06 | 宁波开诚生态技术股份有限公司 | Oil-water separation equipment |
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| JPH03265770A (en) * | 1990-03-15 | 1991-11-26 | Ishikawajima Harima Heavy Ind Co Ltd | Relief valve device |
| US5447174A (en) * | 1993-08-02 | 1995-09-05 | Hydrolux S.A.R.L. | Pilot stage for pressure control valves |
| CN1353261A (en) * | 2000-11-14 | 2002-06-12 | 湘潭工学院 | Pilot-type overflow valve |
| CN101149068A (en) * | 2006-09-18 | 2008-03-26 | 湖南科技大学 | Electricity liquid ratio relief valve |
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2011
- 2011-10-31 CN CN 201110336820 patent/CN102352874B/en not_active Expired - Fee Related
Patent Citations (4)
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| JPH03265770A (en) * | 1990-03-15 | 1991-11-26 | Ishikawajima Harima Heavy Ind Co Ltd | Relief valve device |
| US5447174A (en) * | 1993-08-02 | 1995-09-05 | Hydrolux S.A.R.L. | Pilot stage for pressure control valves |
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Non-Patent Citations (1)
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| 张增猛等: "纯水比例溢流阀静态特性的仿真与试验", 《煤炭学报》 * |
Cited By (12)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102829010A (en) * | 2012-08-16 | 2012-12-19 | 北京润菲利德科技有限公司 | Directly moving type high-flow directional flow servo valve and control system using servo valve |
| CN102829010B (en) * | 2012-08-16 | 2015-11-04 | 北京润菲利德科技有限公司 | Direct acting type large discharge directional flow servovalve and apply the control system of this servovalve |
| CN103047291A (en) * | 2012-12-28 | 2013-04-17 | 扬州锻压机床股份有限公司 | Lubricating oil fine-tuning and throttling structure of precise hydrostatic bearing |
| CN103047291B (en) * | 2012-12-28 | 2015-08-19 | 扬州锻压机床股份有限公司 | A kind of precision static pressure bearing oil fine adjustment flow structure |
| CN104196793A (en) * | 2014-07-31 | 2014-12-10 | 红安安达新材料有限责任公司 | Overflow valve |
| CN109027222A (en) * | 2018-10-24 | 2018-12-18 | 扬州荣德新能源科技有限公司 | A kind of piston and the proportioning valve including it |
| CN109027222B (en) * | 2018-10-24 | 2021-06-25 | 扬州荣德新能源科技有限公司 | Piston and proportional valve comprising same |
| CN109555740A (en) * | 2018-11-09 | 2019-04-02 | 太原理工大学 | A kind of water base proportioning valve and its control method |
| CN109555740B (en) * | 2018-11-09 | 2020-02-04 | 太原理工大学 | Water-based proportional valve and control method thereof |
| CN109798273A (en) * | 2019-03-18 | 2019-05-24 | 杭州诺祥科技有限公司 | A kind of flux matched formula balance fastening system of asymmetric drift |
| CN117509816A (en) * | 2024-01-05 | 2024-02-06 | 宁波开诚生态技术股份有限公司 | Oil-water separation equipment |
| CN117509816B (en) * | 2024-01-05 | 2024-03-29 | 宁波开诚生态技术股份有限公司 | Oil-water separation equipment |
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| CN102352874B (en) | 2013-12-25 |
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